European Journal of Clinical Investigation
0014-2972
1365-2362
Anh Quốc
Cơ quản chủ quản: WILEY , Wiley-Blackwell Publishing Ltd
Lĩnh vực:
BiochemistryClinical BiochemistryMedicine (miscellaneous)
Các bài báo tiêu biểu
Polycythemia vera‐associated pruritus and its management Eur J Clin Invest 2010; 40 (9): 828–834 Abstract Background Pruritus is a defining feature of polycythemia vera (PV) and is seen in approximately 40% of patients. In most cases, the pruritus is characteristically triggered by contact with water (aquagenic) at any temperature.Materials and methods A detailed MEDLINE search for all English language articles related to PV, PV‐associated pruritus and aquagenic pruritus that were published from 1965 till date was carried out.Results Many different treatment options have been tried over the past several decades, including antihistamines, antidepressants, interferon alpha, phlebotomy, phototherapy, iron supplements and myelosuppressive medications, all demonstrating mixed results. Recently, agents that target JAK2 and mammalian target of rapamycin (mTOR) have shown impressive clinical benefit.Conclusion PV‐associated pruritus is a major cause of morbidity amongst patients with PV. Antidepressant medications interfering with serotonin uptake are somewhat efficacious. Cytoreductive therapy is reserved for refractory cases. Targeted therapy with JAK2 and mTOR inhibitors offers renewed hope.
Tập 40 Số 9 - Trang 828-834 - 2010
Normal and low molecular weight heparins: interaction with human platelets Abstract. Porcine mucosal heparin was chemically depolymerized. The depolymerization was stopped at different steps to obtain two low molecular weight (LMW) heparins with a molecular weight of 10 000 and 6000, respectively. The LMW heparins were tested in vitro for anti‐clotting activities and for platelet serotonin release in different systems in comparison with normal heparins, dermatan and heparan sulphate.After addition of various amounts of heparin preparations to washed platelets, no significant release was observed for all tested heparins. On the contrary, different heparins showed an inhibition of serotonin‐release induced by collagen in platelet rich plasma, whereas the ADP‐induced release was increased. The effect on the platelet release appears related to the molecular weight. In fact, it is significant only for normal heparins whereas it is not for LMW heparins. A good relation was observed, also, between anti‐activated factor X activity/antiglobal clotting activity (Xa/APTT) ratio of different heparins and the effect on platelet release.
Tập 13 Số 2 - Trang 135-139 - 1983
Sulphur containing amino acids in chronic renal failure with particular reference to homocystine and cysteine‐homocysteine mixed disulphide Abstract. We measured plasma sulphur amino acids in twenty‐two patients with chronic renal failure and compared the findings with those obtained in twenty‐two normal subjects. In fasting blood (08.00 hours) cysteine‐homocysteine mixed disulphide was significantly increased in the renal patients, mean values (± SD) being 8.2 ± 3.4 and 3.1 ± 1.0 μmol/l respectively (P < 0.001). The increase was positively correlated with reduced renal function, as assessed by serum creatinine (r = 0.62; P < 0.01). Homocystine was detected in nineteen patients, the mean concentration (± SD) being 1.7 ± 0.6 μmol/l; it was not found in any normal subject. Methionine levels were not different but there were significant increases in cystine (P < 0.001) and taurine (P < 0.05) in the patients. Similar values for these amino acids were found in a second blood sample drawn at 16.00 hours. Changes in the other neutral and acidic amino acids measured were in agreement with those reported in chronic azotaemia. We concluded that plasma levels of all the principal sulphur amino acids except methionine are elevated in chronic renal failure emphasizing the importance of the kidney in sulphur excretion. Prolonged accumulation of homocysteine and cysteine‐homocysteine mixed disulphide may be relevant to the development of accelerated vascular disease in patients with chronic renal failure by producing endothelial damage.
Tập 9 Số 4 - Trang 301-307 - 1979
The effects of IGF‐I and IGF‐II on proliferation and differentiation of human osteoblasts and interactions with growth hormone Background We have previously shown that growth hormone (GH) consistently stimulates proliferation of human osteoblasts in vitro . In rat osteoblasts, GH augments the effects of insulin‐like growth factor (IGF) I on cell proliferation and differentiation. We therefore investigated the effects of IGF‐I and ‐II alone and in combination with GH on human osteoblasts in vitro . Methods Human osteoblast‐like cells (HOB) were established from trabecular explants (n = 18) and human marrow stromal cells (HMS) from marrow aspiration (n = 21). The cell cultures were stimulated with IGF‐I or IGF‐II (1, 10 or 100 ng mL−1 ) alone, in combination with hGH (100 ng mL−1 ) or after prestimulation with hGH. Results IGF‐I alone, in combination with hGH and after pretreatment with hGH, increased proliferation of HOB and HMS by 49–190% (P < 0.05–0.01). IGF‐II alone, in combination with hGH and after pretreatment with hGH increased proliferation of HOB by 57–158% (P < 0.01). In HMS only IGF‐II in combination with hGH and after prestimulation with hGH increased proliferation. IGF‐I alone and in combination with hGH decreased alkaline phosphatase (AP) in both cell types. IGF‐II did not affect AP in HOB, but increased AP in HMS, this effect was abolished by hGH. In HOB, collagen production (PICP) was increased by IGF‐II but unaffected by IGF‐I. In HMS, PICP was decreased by IGF‐I and ‐II but increased by hGH. Co‐stimulation further increased PICP. Conclusion IGF‐I and ‐II exerted proliferative effects on both HOB and HMS. Co‐stimulation with GH exhibited synergism in enhancing the proliferative response. In HMS prestimulation improved the proliferative response significantly. The effects of the IGFs on differentiation are more complex and dependent on cell maturation and of the IGF used.
Tập 28 Số 3 - Trang 176-183 - 1998
The Effect of Spironolactone on Transport of Na<sup>+</sup>., K<sup>+</sup> and H<sup>+</sup>. A Microperfusion Study in Rat Main Submaxillary Duct* The epithelium of the main excretory duct of the rat submaxillary gland was used as a target tissue for studies on the effect of a spironolactone on electrolyte transport. The spironolactone decreased net Na+ reabsorption by 27 % and net K+ secretion by 23 %. HCO3 was found to be about 2‐fold accumulated in the duct lumen, which was considered to result from decreased H+ ion secretion. The results can be reconciled with an action of spironolactone on 1) the peritubular Na+ ‐K+ ‐exchange mechanism and 2) the functional coupling of Na+ entry from lumen to cell with K+ and H+ transfer from cell to lumen.
Tập 6 Số 1 - Trang 17-20 - 1976
Vitamin D predictors in polycystic ovary syndrome: a meta-analysis
Tập 47 Số 10 - Trang 746-755 - 2017
Acute inhibitory effect of alcohol on fibrinolysis In contrast to a reduced risk of coronary heart disease (CHD) with light to moderate alcohol consumption, heavy alcohol intake and binge drinking are associated with increased cardiovascular mortality. Alcohol has an acute and profound effect on fibrinolysis that may be relevant to the pathogenesis of CHD. The short‐term effects of a low (two glasses, 250 mL, 20 g ethanol) and a high (six glasses, 750 mL, 60 g ethanol) intake of red wine were studied in male volunteers and compared to the intake of mineral water. To find a threshold for inhibition of fibrinolysis and to study a binge effect, a second experiment was performed comparing the intake of four (500 mL, 40 g ethanol) and eight (1000 mL, 80 g ethanol) glasses of red wine with mineral water. Plasminogen activator inhibitor‐1 (PAI‐1), tissue‐type plasminogen activator (t‐PA), plasmin–antiplasmin (PAP) complexes and clot lysis time were measured. In contrast to the circadian rhythm with an enhanced fibrinolysis in the evening that was found in the mineral water group, an intake above four glasses of wine inhibited fibrinolysis significantly. After the intake of two glasses no significant disturbance of the circadian rhythm was observed. Five hours after the consumption of six glasses of wine, a dramatic increase occurred of PAI‐1 antigen (77 ± 42 μg L−1 vs. − 5 ± 10 μg L−1 in the mineral water controls; P < 0·001) and PAI‐1 activity (27 ± 15 U mL−1 vs. − 2 ± 3 U mL−1 in mineral water controls; P < 0·001). Despite a rise in t‐PA antigen, t‐PA activity dropped (− 0·5 ± 0·2 U mL−1 vs. − 0·1 ± 0·2 in controls; P < 0·001) as did PAP complexes (− 103 ± 55 μg L−1 vs. − 26 ± 57 μg L−1 in controls; P < 0·01). After the consumption of eight glasses of wine, the clot lysis assay indicated continued inhibition of fibrinolysis the following morning. Drinking a large amount of alcohol in the evening results in an acute inhibition of fibrinolysis, persisting the following morning. This may predispose to accelerated atherosclerosis and set the stage for thrombotic coronary events, explaining the higher cardiovascular mortality risk in binge drinkers.
Tập 31 Số 2 - Trang 164-170 - 2001
H<sub>2</sub>‐receptor antagonists are scavengers of oxygen radicals Abstract. Potential oxygen radical scavenging properties of the H2 ‐receptor antagonists cimetidine, ranitidine and famotidine were investigated. These drugs, although ineffective against superoxide anion and hydrogen peroxide, can scavenge hydroxyl radical (OH·) with a very high rate constant, which is about tenfold higher than that of the specific scavenger mannitol for famotidine (1·7 × 1010 mol−1 s−1 ) and cimetidine (1·6 × 1010 mol−1 s−1 ), ranitidine displaying a rate constant of 7·5 × 109 mol−1 s−1 . These OH· scavenging effects are significant beginning from 10, 28 and 100 μmol 1−1 concentration for famotidine, cimetidine and ranitidine, respectively, thus suggesting that the drugs may effectively act as OH· scavengers in vivo especially in the gastric lumen. Only cimetidine can apparently bind and inactivate iron, which further emphasizes its antioxidant capacity. Moreover, all drugs, even at 10 μmol 1−1 concentration, show powerful scavenging effects on hypochlorous acid and monochloramine, which are cytotoxic oxidants arising from inflammatory cells, such as neutrophils. These data suggest that some therapeutical effects of H2 ‐receptor antagonists in peptic ulcer may also be related to their antiradical‐antioxidant capacity, and that these drugs could potentially be used in other disease entities characterized by free radical‐mediated oxidative stress in vivo .
Tập 24 Số 7 - Trang 476-481 - 1994
Effects of omega‐3 fatty acids and/or antioxidants on endothelial cell markers Background Increased expression of cell adhesion molecules and increased procoagulant activity of the vascular endothelium have been postulated to characterize dysfunctional endothelium. The cellular effects of n ‐3 fatty acids (n ‐3 FAs) and antioxidants are still not clarified. Methods In a randomized, factorial two‐by‐two design study, we have investigated 41 male smokers with hyperlipidaemia before and after 6 weeks of supplementation with either n ‐3 FAs (4.8 g daily) or placebo with the addition of antioxidants (150 mg of vitamin C, 75 mg of vitamin E and 15 mg of β‐carotene daily) or placebo with regard to the effects on some endothelial cell markers: thrombomodulin (sTM), von Willebrand factor (vWF), tissue plasminogen activator antigen (tPAag) and soluble forms of the cell adhesion molecules E‐selectin, P‐selectin and vascular cell adhesion molecule 1 (VCAM‐1). Results In the n ‐3 FA group, significant reductions in the plasma levels of vWF (P = 0.034) and sTM (P < 0.001) were demonstrated compared with placebo, whereas increased levels were found for E‐selectin (P = 0.001) and VCAM‐1 (P = 0.010). In the antioxidant group, no differences in changes were noted for any of the variables. Conclusion The reduction in the levels of sTM and vWF with n ‐3 FA supplementation could indicate an improvement with regard to the haemostatic markers of endothelial dysfunction, whereas the simultaneous increase in the soluble forms of E‐selectin and VCAM‐1 may suggest an adverse effect on the inflammatory system. The antioxidants seem to be neutral in their effect on these endothelial cell markers in our study population of smokers. The interpretation of the soluble forms of these molecules are, however, still debatable.
Tập 28 Số 8 - Trang 629-635 - 1998
Post‐prandial lipoprotein metabolism in nephrotic syndrome Abstract. Post‐prandial lipaemia was investigated in a group of nine subjects with nephrotic syndrome by following the concentrations of triglyceride and retinyl palmitate in the d< 1.006 g ml‐1 fraction of plasma after a standard oral fat load containing vitamin A. Lipoprotein lipase and hepatic triglyceride lipase activities were measured in post‐heparin plasma. Subjects with other renal disease but insignificant protein‐uria acted as controls. The time course of the lipaemic response was similar in both groups although individual patients demonstrated a prolonged lipaemia. Overall, there were no significant differences in the rise in triglyceride at 6 h (nephrotic—median 2.53 mmol 1‐1 ; range 0.87–4.76 vs. control 1.88; 0.38–4.12,p = 0.34), the peak concentration of retinyl palmitate (nephrotic 0.87 mg dl‐1 ; 0.27–2.16 vs. control 0.65; 0.24–1.89,P = 0.97) or the areas under the curve from 0.24 h for triglyceride (nephrotic 10.5 mmol. h l‐1 ; 2.9–43.6 vs. control 9.7; 4.3–27.0,P =l.0) or retinyl palmitate (5.5 mg.h dl‐1 ; 1.0–23.4 vs. 4.3; 1.5–12.4,P = 0.7). At baseline, the particles in the d < 1.006 g ml‐1 fraction of plasma from nephrotic subjects had a higher free cholesterol: phospholipid ratio but this difference was no longer apparent 6 h after the test meal. There were no differences in total heparin‐releasable lipase, lipoprotein lipase or hepatic triglyceride lipase activities between the two groups. These data suggest that impaired clearance of chylomicrons is not a major contributor to nephrotic hyperlipidae‐mia in man.
Tập 22 Số 12 - Trang 813-820 - 1992